Image processing apparatus, image processing method, and storage medium, relating to emphasizing a contour region

ABSTRACT

An image processing apparatus includes an identification unit configured to identify a contour region including a contour component in an input image, a determination unit configured to determine a scatter degree of the contour region in the input image, an emphasis processing unit configured to increase, in a case where the scatter degree of the contour region is greater than a determination value, an emphasis degree of the contour region in comparison to a case where the scatter degree is equal to or less than the determination value, and an output unit configured to output, to a display unit, the input image including the contour region in which the emphasis processing unit increases the emphasis degree.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an image processing apparatus, an imageprocessing method, and a storage medium.

Description of the Related Art

Conventionally, there has been known a technique for displaying anin-focus region in an image in a mode different from modes of the otherregions. Japanese Patent Application Laid-Open No. 2001-008065 discussesa technique for executing processing for coloring a contour portionaccording to the degree of clearness of the contour portion of an imageand outputting the image in which an in-focus region is recognizable.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, an image processingapparatus includes an identification unit configured to identify acontour region including a contour component in an image, adetermination unit configured to determine a scatter degree of thecontour region in the image, an emphasis processing unit configured toincrease, in a case where the scatter degree of the contour region isgreater than a first predetermined value, an emphasis degree of thecontour region in comparison to a case where the scatter degree is equalto or less than the first predetermined value, and an output unitconfigured to output, to a display unit, the image including the contourregion in which the emphasis processing unit increases the emphasisdegree.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a configuration of an imagedisplay system according to a first exemplary embodiment.

FIG. 2 is a diagram illustrating an example of a contour region in aninput image.

FIG. 3A is a diagram illustrating an example of a processing imageincluding a contour region.

FIG. 3B is a diagram illustrating an example of a processing imageincluding a contour region on which emphasis processing is executed.

FIG. 4 is a diagram illustrating an example of a combined image in whichemphasis processing is executed on a contour region.

FIG. 5A is a diagram illustrating another example of emphasis processingwith respect to a contour region.

FIG. 5B is a diagram illustrating another example of combined image inwhich emphasis processing is executed on a contour region.

FIG. 6A is a diagram illustrating examples of contour regions includedin a plurality of divided regions.

FIG. 6B is a diagram illustrating an example of a combined image inwhich emphasis processing is executed on contour regions included in aplurality of divided regions.

FIG. 7 is a flowchart illustrating processing steps from receiving animage signal of an input image to outputting a combined image.

FIG. 8A is a diagram illustrating another example of a contour region inan input image.

FIG. 8B is a diagram illustrating another example of a combined image inwhich emphasis processing is executed on a contour region.

DESCRIPTION OF THE EMBODIMENTS Configuration of Image Display System S

A first exemplary embodiment will be described below. FIG. 1 is a blockdiagram illustrating a configuration of an image display system S. Theimage display system S according to the present exemplary embodimentwill be described below. The image display system S is a system fordisplaying an image in which a predetermined region in the image isemphasized.

The image display system S includes an image processing apparatus 10 anda display device 20. For example, the image processing apparatus 10 andthe display device 20 are connected to each other via a cable conformingto the DisplayPort standards.

For example, the image processing apparatus 10 may be computer thatoutputs an image in which a predetermined region in the image isemphasized to the display device 20. For example, the display device 20may be a display having a liquid crystal panel or an organic electroluminescence (EL) panel, which displays an image based on image datareceived from the image processing apparatus 10. In addition, the term“image” used in the present specification includes a static image and amoving image (video image).

Hereinafter, a configuration and an operation of the image processingapparatus 10 will be described in detail with reference to FIG. 1.

The image processing apparatus 10 includes an acquisition unit 100, astorage unit 200, and a control unit 300.

The acquisition unit 100 serves as an interface for acquiring image dataof an image (hereinafter, referred to as “input image”) received from anexternal device (not illustrated) such as an imaging device. Forexample, the acquisition unit 100 may be a universal serial bus (USB)interface or a local area network (LAN) interface.

The storage unit 200 is a storage medium such as a read only memory(ROM), a random access memory (RAM), or a hard disk. The storage unit200 stores image data of the input image, a program executed by thecontrol unit 300, and various kinds of data generated by the controlunit 300.

The control unit 300 is a central processing unit (CPU) for example, andfunctions as an identification unit 301, a determination unit 302, aspecifying unit 303, an emphasis processing unit 304, and an output unit305 by executing a program stored in the storage unit 200. Hereinafter,various functional units provided by the control unit 300 will bedescribed.

The identification unit 301 identifies a contour region including acontour component in the input image based on the image data acquired bythe acquisition unit 100. Specifically, the identification unit 301analyzes a frequency component in the image data to detect a contourcomponent including a high-frequency component equal to or greater thana predetermined threshold value, and identifies a region including thecontour component as a contour region. For example, the identificationunit 301 divides the image into a plurality of regions, inputs the imagedata to a band-pass filter at each divided region, and identifies thecontour region based on the image data that has passed the band-passfilter. From the pixels included in the image data, the identificationunit 301 may identify, as contour components, pixels in which density orcolor thereof is considerably changed by a predetermined value incomparison to that of adjacent pixels, and may identify, as a contourregion, a region in which the identified pixels continuously exist at aninterval equal to or less than a predetermined distance. As describedabove, the identification unit 301 can identify a contour line includedin an in-focus region.

FIG. 2 is a diagram illustrating an example of the contour region in theinput image. In the example illustrated in FIG. 2, contour regions 11 to14 in an input image A identified by the identification unit 301 arerespectively indicated by dotted lines. The identification unit 301selects one pixel from among the pixels included in each of the contourregions 11 to 14 to identify a position of the selected pixel as acontour position corresponding to each of the contour regions 11 to 14.For example, the identification unit. 301 selects a position of a centerof gravity at each of the contour regions 11 to 14. In the exampleillustrated in FIG. 2, contour positions 21 to 24 respectivelycorresponding to the contour regions 11 to 14 in the input image A areillustrated. The identification unit 301 notifies the determination unit302 of contour position information indicating coordinate information ofthe contour positions 21 to 24 in the input image A. Further, theidentification unit 301 notifies the specifying unit 303 of contourregion information indicating a position of each of the pixels includedin the contour regions 11 to 14.

The determination unit 302 determines a degree to which the contourregions are scattered in the input image (hereinafter, referred to as“scatter degree”). For example, the determination unit 302 calculates anaverage value of distances between a plurality of contour positionsbased on the contour position information notified from theidentification unit 301. Then, the determination unit 302 determines thecalculated average value as the scatter degree. Specifically, thedetermination unit 302 determines whether the average value of distancesbetween the contour positions exceeds a previously set determinationvalue L (i.e., first predetermined value). For example, when the averagevalue of the distances between the contour positions 21, 22, 23, and 24exceeds the determination value L in the example illustrated in FIG. 2,the determination unit 302 determines that the scatter degree of thecontour region is high.

In addition, a method in which the determination unit 302 determines thescatter degree of the contour region is not limited to the above. Thedetermination unit 302 may calculates a polygonal area having thecontour positions 21, 22, 23, and 24 as vertexes thereof to determinethe scatter degree based on the calculated area. For example, when avalue of a ratio of the number of pixels included in the polygonalfigure to the number of pixels of the input image exceeds a previouslyset determination value N, the determination unit 302 determines thatthe scatter degree of the contour region is high. On the other hand,when the value of the ratio thereof is equal to or less than thedetermination value N, the determination unit 302 determines that thescatter degree of the contour region is low.

Subsequently, the determination unit 302 notifies the emphasisprocessing unit 304 of the determination result of the scatter degree.For example, as a determination result, the determination unit 302notifies the emphasis processing unit 304 of information indicating thatthe scatter degree is greater than the determination value L, orinformation indicating that the scatter degree is equal to or less thanthe determination value L. Alternatively, the determination unit 302 maynotify the emphasis processing unit 304 of a numerical value indicatingthe scatter degree as a determination result.

The specifying unit 303 specifies the number of pixels included in thecontour region by calculating a total number of pixels included in thecontour region indicated by the contour region information notified fromthe identification unit 301. The number of pixels included in thecontour region is used for identifying a size of the contour region anda ratio of the contour region with respect to the entire input image.The specifying unit 303 notifies the emphasis processing unit 304 of thetotal number of pixels included in the contour region.

The emphasis processing unit 304 executes processing for emphasizing thecontour region. For example, the emphasis processing unit 304 emphasizesthe contour region by darkening the color of the contour line orthickening the contour line. The emphasis processing unit 304 darkensthe color of the contour line by changing a pixel value of the pixel inthe contour region from a pixel value of the input image. The emphasisprocessing unit 304 thickens the contour line by changing the number ofpixels the pixel values of which are to be changed.

Based on the determination result notified from the determination unit302, the emphasis processing unit 304 sets a degree to which the contourregion is emphasized (hereinafter, referred to as “emphasis degree”).For example, the emphasis degree may be a degree to which a pixel valueof the pixel in the contour region or a pixel value of the pixel in avicinity of the contour region is changed, or may be a degree to whichthe number of pixels the pixel values of which are to be changed ischanged. In a case where the scatter degree of the contour region isgreater than the previously set determination value L, the emphasisprocessing unit 304 increases the emphasis degree of the contour regionin comparison to a case where the scatter degree thereof is equal to orless than the determination value L. For example, the emphasisprocessing unit 304 increases the emphasis degree of the contour regionby changing a thickness of the contour line corresponding to the contourcomponent in order to emphasize the contour line.

The emphasis processing unit 304 executes the emphasis processing on thecontour region by using the set emphasis degree and generates a combinedimage in which the contour region in the input image is emphasized.Specifically, based on the emphasis degree, the emphasis processing unit304 generates the combined image by changing a pixel value of the pixelin the contour region in the input image A or a pixel value of the pixelin a vicinity of the contour region. More specifically, the emphasisprocessing unit 304 generates a processing image by extracting a pixelin the contour region or a pixel in a vicinity of the contour region,and generates the combined image by combining an image after changingthe pixel value of the processing image with the input image.

FIG. 3A is a diagram illustrating an example of the processing imageincluding the contour region in the example illustrated in FIG. 3A,contour regions 25 to 28 allocated in the processing image, whichrespectively correspond to the contour regions 11 to 14 of the inputimage A illustrated in FIG. 2, are indicated by dotted lines. Theemphasis processing unit 304 executes the emphasis processing on thecontour regions 25 to 28 in the processing image by using the previouslyset emphasis degree.

FIG. 3B is a diagram illustrating an example of the processing imageincluding the contour regions on which the emphasis processing isexecuted. In the example illustrated in FIG. 3B, the contour regions 25to 28 in the example of FIG. 3A are thickened and emphasized by theemphasis processing unit 304 through the emphasis processing, which arerespectively illustrated as contour regions 31 to 34. The emphasisprocessing unit 304 combines the processing image on which the emphasisprocessing of the contour region is executed and the input image togenerate a combined image. For example, the emphasis processing unit 304executes combining processing for superimposing the contour regions 31to 34 thickened and emphasized in the processing image illustrated inFIG. 3B onto the input image A to generate the combined image.

FIG. 4 is a diagram illustrating an example of the combined image inwhich the emphasis processing is executed on the contour regions. In theexample of FIG. 4, the contour regions 31 to 34 that are emphasized tobe thicker than the contour regions 11 to 14 are illustrated instead ofthe contour regions 11 to 14 in FIG. 2, and thus the visibility of thecontour regions 31 to 34 is improved in comparison to that of thecontour regions 11 to 14.

When the scatter degree is greater than the determination value L, theemphasis processing unit 304 may set a magnitude of the emphasis degreeof the contour region according to a magnitude of the scatter degree.For example, when a value of the scatter degree notified from thedetermination unit 302 is greater than the determination value L, theemphasis processing unit 304 sets the magnitude of the emphasis degreein proportion to the magnitude of the value of scatter degree. Forexample, in a case where the thickness of the contour dine is set as theemphasis degree of the contour region, the emphasis processing unit 304sets the emphasis degree to emphasize the contour region to be thickerwhen the scatter degree of the contour region is greater.

Further, the emphasis processing unit 304 may set the emphasis degree ofthe contour region based on the number of pixels the contour regioninput by the specifying unit 303 and the scatter degree of the contourregion determined by the determination unit 302. For example, theemphasis processing unit 304 may increase the emphasis degree of thecontour region when the number of pixels specified by the specifyingunit 303 is equal to or less than a previously set reference number X(i.e., first predetermined number), and the scatter degree of thecontour region determined by the determination unit 302 is greater thanthe determination value L.

With this configuration, with respect to the contour regions that aresmall and scattered in the input image, the emphasis processing unit 304can increase the degree of emphasis processing. Therefore, the emphasisprocessing unit 304 can effectively emphasize the contour regions thatare less visible as they are small and scattered in the input image.Further, the emphasis processing unit 304 may reduce the emphasis degreeof the contour region if the number of pixels included in the contourregion calculated by the specifying unit 303 is greater than thepreviously set reference number X, and the scatter degree of the contourregion is equal to or less than the determination value L.

FIG. 5A is a diagram illustrating another example of the contour regionin the input image. In the example illustrated in FIG. 5A, a contourregion 15 as a contour of a head of a person as an object in an inputimage B is indicated by a dotted line. For example, when the number ofpixels included in the contour region 15 illustrated in FIG. 5A isgreater than the reference number X, and the scatter degree thereof isequal to or less than the determination value L, the emphasis processingunit 304 makes the emphasis degree of the contour region 15 be smallerthan the emphasis degree that is to be set thereto when the scatterdegree is greater than the determination value L.

FIG. 5B is a diagram illustrating another example of the combined imagein which the emphasis processing is executed on the contour region. Inthe example in FIG. 5B, the contour region 15 of FIG. 5A is emphasizedand illustrated as a contour region. 35 that is indicated by adashed-dotted line. The contour region 35 is a region on which theemphasis processing is executed at the emphasis degree of a small value.Therefore, the emphasis degree of the contour region 35 is suppressed incomparison to that of the contour regions 31 to 34 illustrated in FIG.4, on which the emphasis processing is executed at the emphasis degreeof a large value.

Further, in the above-described example, although the emphasisprocessing unit 304 sets one emphasis degree with respect to each inputimage, the configuration is not limited thereto. For example, theidentification unit 301 may divide the input image into a plurality ofdivided regions and identify the contour region in each of the dividedregions, so that the emphasis processing unit 304 may increase theemphasis degree of the contour region included in the divided region inwhich the scatter degree is greater than the determination value L fromamong the plurality of divided regions.

FIG. 6A is a diagram illustrating the contour regions included in aplurality of divided regions. In the example in FIG. 6A, a contourregion 16 as a contour of the head of a person as an object and twocontour regions 17 and 18 in a background as an object are indicated bydotted lines in an input image C. For example, when the emphasisprocessing is executed on the contour regions in the input image C,first, the identification, unit 301 divides the input image C into aplurality of divided regions C1 to C4 and identifies a contour region ineach of the divided regions C1 to C4. Further, the determination unit302 determines the scatter degree of the contour region in each of thedivided regions C1 to C4.

Next, the emphasis processing unit 304 determines the emphasis degreebased on the size of the contour region and the determination result ofthe scatter degree in each the divided regions C1 to C4. In the exampleillustrated in FIG. 6A, because the number of pixels in each of thecontour regions 17 and 18 included in the divided region C3 is equal toor less than the reference number X, and the scatter degree is greaterthan the previously set determination value L, the emphasis processingunit 304 increases the emphasis degree with respect to the contourregions 17 and 18 included in the divided region C3. Further, becausethe number of pixels in the contour region 16 included in the dividedregions C1 and C4 is greater than the reference number X, and thescatter degree is equal to or less than the determination value L, theemphasis processing unit 304 does not increase the emphasis degree withrespect to the contour region 16 included in the divided regions C1 andC4.

FIG. 6B is a diagram illustrating an example of a combined image inwhich the emphasis processing is executed on the contour regionsincluded in the divided region C3. In the example illustrated in FIG.6B, contour regions 37 and 38 included in the divided region C3 areemphasized to be thicker than a contour region 36. With thisconfiguration, even if a region in which the contour components areconcentrated and a region in which the contour components are scatteredare intermingled in the input image, the emphasis processing at greateremphasis degree can be executed on the region in which the contourcomponents are scattered.

Further, in the above-described example, the emphasis processing unit304 increases only the emphasis degree with respect to the contourregions 17 and 18 included in the divided region C3. However, theconfiguration is not limited thereto. For example, the emphasisprocessing unit 304 may execute the emphasis processing on the contourregion included in each of the divided regions using the emphasis degreethat is gradually set to each of the divided regions.

Referring back to FIG. 1, the output unit 305 outputs the image data ofthe combined image generated by the emphasis processing unit 304 to thedisplay device 20. With this processing, a user of the image displaysystem S can confirm the combined image displayed on the display device20 in which the contour region is emphasized to become visiblefavorably.

Further, in the above-described example, the emphasis processing unit304 executes the emphasis processing for thickening the contour regionaccording to the scatter degree. However, the configuration is notlimited thereto. For example, the emphasis processing unit 304 mayexecute the emphasis processing by changing the color of the contourregion according to the scatter degree.

Processing Steps in Image Display System S

Subsequently, description will be given to processing steps foroutputting the combined image based on the image signal of the inputimage, executed by the image display system S. FIG. 7 is a flowchartillustrating processing steps from receiving the image signal tooutputting the combined image.

First, in step S101, the acquisition unit 100 of the image processingapparatus 10 acquires the image data of the input image. Next, in stepS102, the identification unit 301 identifies a contour region includedin the image data. The identification unit 301 notifies thedetermination unit 302 of contour position information of the contourregion, and notifies the specifying unit 303 of contour regioninformation.

Next, in step S103, based on the contour position information notifiedfrom the identification unit 301, the determination unit 302 determinesthe scatter degree of the contour region in the input image. Thedetermination unit 302 notifies the emphasis processing unit 304 of adetermination result.

Next, in step S104, based on the contour region information notifiedfrom the identification unit 301, the specifying unit 303 calculates thenumber of pixels included in the contour region, and notifies theemphasis processing unit 304 of the number of pixels. In addition, thedetermination unit 302 may determine the scatter degree of the contourregion after the specifying unit calculates the number of pixels. Inother words, the processing in steps S103 and S104 can be executed inarbitrary order.

Next, if the scatter degree of the contour region is greater than thedetermination value L (YES in step S105), the processing proceeds tostep S106. In step S106, the emphasis processing unit 304 determineswhether the number of pixels in the contour region is equal to or lessthan the reference number X. If the number of pixels in the contourregion is equal to or less than the reference number X (YES in stepS106), the processing proceeds to step S107. In step S107, the emphasisprocessing unit 304 sets the emphasis degree to a large value.

On the other hand, if the scatter degree of the contour region is equalto or less than the determination value L (NO in step S105), or if thenumber of pixels is greater than the reference number X (NO in stepS106), the processing proceeds to step S108. In step S108, the emphasisprocessing unit 304 sets the emphasis degree of the emphasis processingto a small value. In addition, the emphasis processing unit 304 may setthe emphasis degree of the emphasis processing to a different valuedepending on the case where the scatter degree is greater than thedetermination value L or the case where the number of pixels is equal toor less than the reference number X. For example, in a case where thescatter degree is greater than the determination value L, the emphasisprocessing unit 304 may set the emphasis degree of the emphasisprocessing to a larger value in comparison to the case where the numberof pixels is equal to or less than the reference number X.

Next, in step S109, the emphasis processing unit 304 executes theemphasis processing on the contour region using the set emphasis degreeand generates a combined image. Subsequently, in step S110, the outputunit 305 outputs the combined image to the display device 20.

Further, in the above-described exemplary embodiment, description hasbeen given to a configuration including the processing step forcalculating the number of pixels included in the contour region (i.e.,step S104) and the processing step for determining whether the number ofpixels in the contour region is equal to or less than the referencenumber X (i.e., step S106). However, the image processing apparatus 10may execute the processing without taking the processing steps S104 andS106.

Effect of the First Exemplary Embodiment

As described above, the image processing apparatus 10 according to thepresent exemplary embodiment identifies the contour region in the inputimage and determines the scatter degree of the contour region. Then, ina case where the scatter degree of the contour region is greater thanthe determination value L, the image processing apparatus 10 executesthe emphasis processing using the greater emphasis degree of the contourregion in comparison to the case where the scatter degree is equal to orless than the determination value L, and outputs the combined imageincluding the contour region on which the emphasis processing isexecuted to the display device 20. With this configuration, the contourregions scattered in the combined image can be emphasized, and thus thevisibility of the contour regions scattered in the combined image isimproved.

Hereinafter, a second exemplary embodiment will be described. In theimage display system S according to the first exemplary embodiment, whenthe scatter degree of the contour region is greater than thedetermination value L, the emphasis processing unit 304 executes theemphasis processing by changing a pixel value of the pixel in thecontour region or in a vicinity of the contour region. On the contrary,the image display system S according to the present exemplary embodimentis different in that the emphasis processing unit 304 adds an imagearound the contour region in a case where the number of pixels in thecontour region calculated by the specifying unit 303 is equal to or lessthan a reference number Y (i.e., second predetermined number) that isless than the reference number X, and the scatter degree of the contourregion is equal to or less than a determination value M (i.e., secondpredetermined value) that is less than the determination value L.

FIG. 8A is a diagram illustrating another example of the contour regionin the input image. In the example illustrated in FIG. 8A, a contourregion 19 as a contour of a nose of a person as an object in an inputimage D is indicated by a dotted line. In the example illustrated inFIG. 8A, the pixels included in the contour region 19 are small andconcentrated in a certain range in the image, so that visibility of thecontour region 19 is deteriorated.

For example, when the emphasis processing is to be executed on thecontour region 19 illustrated in the example in FIG. 8A, the emphasisprocessing unit 304 executes the emphasis processing for superimposingan image W onto a region including the contour region 19 in a case wherethe number of pixels included in the contour region 19 detected from theinput image D is equal to or less than the reference number Y and thescatter degree of the contour region 19 is equal to or less thandetermination value M.

FIG. 8B is a diagram illustrating an example of the combined image inwhich the emphasis processing is executed on the contour region. In theexample illustrated in FIG. 8B, the image W is superimposed on theregion including the contour region 19, and thus visibility of thecontour region 19 is improved in comparison to the example illustratedin FIG. 8A. With this configuration, even if the contour region is lessvisible because the scatter degree of the contour region in the inputimage is low and an area occupied by the contour region is small, it ispossible to efficiently improve the visibility of the contour region.

Further, in the present exemplary embodiment, the emphasis processingunit 304 adds a rectangular image as the image W used for identifyingthe contour region. However, the configuration is not limited thereto.For example, the image W used for identifying the contour region may bean image of an arrow that indicates the contour region. Further, thecolor of the image W may be different from the color of the contourregion.

Effect of the Second Exemplary Embodiment

As described above, when the scatter degree of the contour regiondetected from the input, image is equal to or less than thedetermination value N, and the number of pixels included in the contourregion is equal to or less than the reference number Y, the imageprocessing apparatus 10 according to the second exemplary embodimentadds an image used for identifying the contour region. With thisconfiguration, the region including the contour region in the image canbe visualized, and thus it is possible to generate a combined image inwhich visibility of the contour region is improved efficiently.

For example, if the area occupied by the contour region in the inputimage is small and visibility thereof is low even though the processingfor emphasizing the contour region itself is executed, the visibility ofthe contour region in the combined image can be improved bysuperimposing and displaying the image for identifying the contourregion thereon.

While the present invention has been described with reference to theexemplary embodiments, a technical scope of the present invention is notlimited to that described in the above exemplary embodiments, and manyvariations and modifications are possible within the scope of thepresent invention.

Other Embodiments

Embodiment(s) of the present invention can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment (s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment (s) and/or controlling the one or more circuits to performthe functions of one or more of the above-described embodiment (s). Thecomputer may comprise one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (PAM), a read only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blueray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2015-113959, filed Jun. 4, 2015, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An image processing apparatus comprising: atleast one processor; and at least one memory storing a program which,when executed by the at least one processor, causes the image processingapparatus to: identify a plurality of contour regions, each respectivelyincluding a contour component, in an image; determine a scatter degreeof the plurality of contour regions in the image; increase, in a casewhere the scatter degree of the plurality of contour regions is greaterthan a first predetermined value, an emphasis degree of the plurality ofcontour regions in comparison to a case where the scatter degree isequal to or less than the first predetermined value; and output, to adisplay unit, the image including the plurality of contour regions, inwhich the emphasis degree of the plurality of contour regions is theincreased emphasis degree, wherein the scatter degree is a degree towhich the contour regions are spatially scattered in the image.
 2. Theimage processing apparatus according to claim 1, wherein a number ofpixels included in the plurality of contour regions is specified, andwherein, in a case where the specified number of pixels is equal to orless than a first predetermined number and the scatter degree of theplurality of contour regions is greater than the first predeterminedvalue, the emphasis degree of the plurality of contour regions isincreased.
 3. The image processing apparatus according to claim 2,wherein, in a case where the specified number of pixels is equal to orless than a second predetermined number that is less than the firstpredetermined number and the scatter degree of the plurality of contourregions is equal to or less than a second predetermined value that isless than the first predetermined value, an additional image used foridentifying the plurality of contour regions is combined to the image.4. The image processing apparatus according to claim 1, wherein, in acase where the scatter degree is greater than the first predeterminedvalue, the emphasis degree of the plurality of contour regions is set toa magnitude according to a magnitude of the scatter degree.
 5. The imageprocessing apparatus according to claim 1, wherein the image is dividedinto a plurality of divided regions and a contour region in each of thedivided regions is identified, and wherein an emphasis degree of acontour region included in a divided region, in which the scatter degreeis greater than the first predetermined value from among the pluralityof divided regions, is increased.
 6. The image processing apparatusaccording to claim 1, wherein each of the plurality of contour regionsis identified by detecting a contour component in the image, and whereinthe emphasis degree of the plurality of contour regions is increased bychanging a thickness of a contour line corresponding to the detectedcontour component in the image.
 7. An image processing method using aprocessor to perform steps of: identifying a plurality of contourregions, each respectively including a contour component, in an image;determining a scatter degree of the plurality of contour regions in theimage; increasing, in a case where the scatter degree of the pluralityof contour regions is greater than a first predetermined value, theemphasis degree of the plurality of contour regions in comparison to acase where the scatter degree is equal to or less than the firstpredetermined value; and outputting, to a display unit, the imageincluding the plurality of contour regions, in which the emphasis degreeof the plurality of contour regions is the increased emphasis degree,wherein the scatter degree is a degree to which the contour regions arespatially scattered in the image.
 8. The image processing methodaccording to claim 7, wherein the processor further performs a step ofspecifying a number of pixels included in the plurality of contourregions, and wherein, in a case where the specified number of pixels isequal to or less than a first predetermined number and the scatterdegree of the plurality of contour regions is greater than the firstpredetermined value, the emphasis degree of the plurality of contourregions is increased.
 9. The image processing method according to claim8, wherein, in a case where the specified number of pixels is equal toor less than a second predetermined number that is less than the firstpredetermined number and the scatter degree of the plurality of contourregions is equal to or less than a second predetermined value that isless than the first predetermined value, an additional image used foridentifying the plurality of contour regions is combined to the imagewhen the emphasis degree of the plurality of contour regions isincreased.
 10. The image processing method according to claim 7,wherein, in a case where the scatter degree is greater than the firstpredetermined value, the emphasis degree of the plurality of contourregions is set to a magnitude according to a magnitude of the scatterdegree when the emphasis degree of the plurality of contour regions isincreased.
 11. The image processing method according to claim 7,wherein, when the plurality of contour regions is identified, the imageis divided into a plurality of divided regions, and a contour region ineach of the divided regions is identified, and wherein, when theemphasis degree is increased, an emphasis degree of a contour regionincluded in a divided region, in which the scatter degree is greaterthan the first predetermined value, from among the plurality of dividedregions, is increased.
 12. The image processing method according toclaim 7, wherein, when the plurality of contour regions is identified,each of the plurality of contour regions is identified by detecting acontour component in the image, and wherein, when the emphasis degree isincreased, the emphasis degree of the plurality of contour regions isincreased by changing a thickness of a contour line corresponding to thedetected contour component in the image.
 13. A non-transitorycomputer-readable storage medium storing a program for causing acomputer to execute an image processing method comprising: identifying aplurality of contour regions, each respectively including a contourcomponent, in an image; determining a scatter degree of the plurality ofcontour regions in the image; increasing, in a case where the scatterdegree of the plurality of contour regions is greater than a firstpredetermined value, an emphasis degree of the plurality of contourregions in comparison to a case where the scatter degree is equal to orless than a first predetermined value; and outputting, to a displayunit, the image including the plurality of contour regions, in which theemphasis degree of the plurality of contour regions is the increasedemphasis degree, wherein the scatter degree is a degree to which thecontour regions are spatially scattered in the image.
 14. The imageprocessing apparatus according to claim 1, wherein the scatter degree isdetermined based on spatial distances between the plurality of contourregions in the image.
 15. The image processing apparatus according toclaim 14, wherein the scatter degree is determined based on an averagevalue of spatial distances between the plurality of contour regions inthe image.
 16. The image processing method according to claim 7, whereinthe scatter degree is determined based on spatial distances between theplurality of contour regions in the image.
 17. The image processingmethod according to claim 16, wherein the scatter degree is determinedbased on an average value of spatial distances between the plurality ofcontour regions in the image.